From 0293214b8c5bf56a095d0a39c5821c9da66dd566 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 6 Dec 2013 17:54:26 +0100 Subject: qdev: allow both pre- and post-order vists in qdev walking functions Resetting should be done in post-order, not pre-order. However, qdev_walk_children and qbus_walk_children do not allow this. Fix it by adding two extra arguments to the functions. Signed-off-by: Paolo Bonzini Signed-off-by: Michael S. Tsirkin --- hw/core/qdev.c | 45 +++++++++++++++++++++++++++++++++------------ 1 file changed, 33 insertions(+), 12 deletions(-) (limited to 'hw/core') diff --git a/hw/core/qdev.c b/hw/core/qdev.c index e374a9399f..5ddf1aaad0 100644 --- a/hw/core/qdev.c +++ b/hw/core/qdev.c @@ -240,12 +240,12 @@ static int qbus_reset_one(BusState *bus, void *opaque) void qdev_reset_all(DeviceState *dev) { - qdev_walk_children(dev, qdev_reset_one, qbus_reset_one, NULL); + qdev_walk_children(dev, qdev_reset_one, qbus_reset_one, NULL, NULL, NULL); } void qbus_reset_all(BusState *bus) { - qbus_walk_children(bus, qdev_reset_one, qbus_reset_one, NULL); + qbus_walk_children(bus, qdev_reset_one, qbus_reset_one, NULL, NULL, NULL); } void qbus_reset_all_fn(void *opaque) @@ -337,49 +337,70 @@ BusState *qdev_get_child_bus(DeviceState *dev, const char *name) return NULL; } -int qbus_walk_children(BusState *bus, qdev_walkerfn *devfn, - qbus_walkerfn *busfn, void *opaque) +int qbus_walk_children(BusState *bus, + qdev_walkerfn *pre_devfn, qbus_walkerfn *pre_busfn, + qdev_walkerfn *post_devfn, qbus_walkerfn *post_busfn, + void *opaque) { BusChild *kid; int err; - if (busfn) { - err = busfn(bus, opaque); + if (pre_busfn) { + err = pre_busfn(bus, opaque); if (err) { return err; } } QTAILQ_FOREACH(kid, &bus->children, sibling) { - err = qdev_walk_children(kid->child, devfn, busfn, opaque); + err = qdev_walk_children(kid->child, + pre_devfn, pre_busfn, + post_devfn, post_busfn, opaque); if (err < 0) { return err; } } + if (post_busfn) { + err = post_busfn(bus, opaque); + if (err) { + return err; + } + } + return 0; } -int qdev_walk_children(DeviceState *dev, qdev_walkerfn *devfn, - qbus_walkerfn *busfn, void *opaque) +int qdev_walk_children(DeviceState *dev, + qdev_walkerfn *pre_devfn, qbus_walkerfn *pre_busfn, + qdev_walkerfn *post_devfn, qbus_walkerfn *post_busfn, + void *opaque) { BusState *bus; int err; - if (devfn) { - err = devfn(dev, opaque); + if (pre_devfn) { + err = pre_devfn(dev, opaque); if (err) { return err; } } QLIST_FOREACH(bus, &dev->child_bus, sibling) { - err = qbus_walk_children(bus, devfn, busfn, opaque); + err = qbus_walk_children(bus, pre_devfn, pre_busfn, + post_devfn, post_busfn, opaque); if (err < 0) { return err; } } + if (post_devfn) { + err = post_devfn(dev, opaque); + if (err) { + return err; + } + } + return 0; } -- cgit v1.2.1 From dcc209314afdaeec42f1e2a7bbf37eec3ace23de Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Fri, 6 Dec 2013 17:54:27 +0100 Subject: qdev: switch reset to post-order Post-order is the only sensible direction for the reset signals. For example, suppose pre-order is used and the parent has some data structures that cache children state (for example a list of active requests). When the reset method is invoked on the parent, these caches could be in any state. If post-order is used, on the other hand, these will be in a known state when the reset method is invoked on the parent. This change means that it is no longer possible to block the visit of the devices, so the callback is changed to return void. This is not a problem, because PCI was returning 1 exactly in order to achieve the same ordering that this patch implements. PCI can then rely on the qdev core having sent a "reset signal" (whatever that means) to the device, and only do the PCI-specific initialization with pci_do_device_reset. MST: fixed up virtio-ccw Signed-off-by: Paolo Bonzini Signed-off-by: Michael S. Tsirkin --- hw/core/qdev.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'hw/core') diff --git a/hw/core/qdev.c b/hw/core/qdev.c index 5ddf1aaad0..d2ffe35710 100644 --- a/hw/core/qdev.c +++ b/hw/core/qdev.c @@ -233,19 +233,19 @@ static int qbus_reset_one(BusState *bus, void *opaque) { BusClass *bc = BUS_GET_CLASS(bus); if (bc->reset) { - return bc->reset(bus); + bc->reset(bus); } return 0; } void qdev_reset_all(DeviceState *dev) { - qdev_walk_children(dev, qdev_reset_one, qbus_reset_one, NULL, NULL, NULL); + qdev_walk_children(dev, NULL, NULL, qdev_reset_one, qbus_reset_one, NULL); } void qbus_reset_all(BusState *bus) { - qbus_walk_children(bus, qdev_reset_one, qbus_reset_one, NULL, NULL, NULL); + qbus_walk_children(bus, NULL, NULL, qdev_reset_one, qbus_reset_one, NULL); } void qbus_reset_all_fn(void *opaque) -- cgit v1.2.1